app.py

try:
    import spaces
    GPU = spaces.GPU
    print("spaces GPU is available")
except ImportError:
    def GPU(func):
        return func

import os
import subprocess

# def install_cuda_toolkit():
#     # CUDA_TOOLKIT_URL = "https://developer.download.nvidia.com/compute/cuda/11.8.0/local_installers/cuda_11.8.0_520.61.05_linux.run"
#     CUDA_TOOLKIT_URL = "https://developer.download.nvidia.com/compute/cuda/12.4.0/local_installers/cuda_12.4.0_550.54.14_linux.run"
#     CUDA_TOOLKIT_FILE = "/tmp/%s" % os.path.basename(CUDA_TOOLKIT_URL)
#     subprocess.call(["wget", "-q", CUDA_TOOLKIT_URL, "-O", CUDA_TOOLKIT_FILE])
#     subprocess.call(["chmod", "+x", CUDA_TOOLKIT_FILE])
#     subprocess.call([CUDA_TOOLKIT_FILE, "--silent", "--toolkit"])
    
#     os.environ["CUDA_HOME"] = "/usr/local/cuda"
#     os.environ["PATH"] = "%s/bin:%s" % (os.environ["CUDA_HOME"], os.environ["PATH"])
#     os.environ["LD_LIBRARY_PATH"] = "%s/lib:%s" % (
#         os.environ["CUDA_HOME"],
#         "" if "LD_LIBRARY_PATH" not in os.environ else os.environ["LD_LIBRARY_PATH"],
#     )
#     # Fix: arch_list[-1] += '+PTX'; IndexError: list index out of range
#     os.environ["TORCH_CUDA_ARCH_LIST"] = "8.0;8.6"

#     print("Successfully installed CUDA toolkit at: ", os.environ["CUDA_HOME"])

#     subprocess.call('rm /usr/bin/gcc', shell=True)
#     subprocess.call('rm /usr/bin/g++', shell=True)
#     subprocess.call('rm /usr/local/cuda/bin/gcc', shell=True)
#     subprocess.call('rm /usr/local/cuda/bin/g++', shell=True)

#     subprocess.call('ln -s /usr/bin/gcc-11 /usr/bin/gcc', shell=True)
#     subprocess.call('ln -s /usr/bin/g++-11 /usr/bin/g++', shell=True)

#     subprocess.call('ln -s /usr/bin/gcc-11 /usr/local/cuda/bin/gcc', shell=True)
#     subprocess.call('ln -s /usr/bin/g++-11 /usr/local/cuda/bin/g++', shell=True)

#     subprocess.call('gcc --version', shell=True)
#     subprocess.call('g++ --version', shell=True)

# install_cuda_toolkit()

# subprocess.run('pip install git+https://github.com/nerfstudio-project/gsplat.git@32f2a54d21c7ecb135320bb02b136b7407ae5712 --no-build-isolation --use-pep517', env={'CUDA_HOME': "/usr/local/cuda", "TORCH_CUDA_ARCH_LIST": "8.0;8.6"}, shell=True)

from flask import Flask, jsonify, request, send_file, render_template
import base64
import io
from PIL import Image
import torch
import numpy as np
import os
import argparse
import imageio
import json

import time
import threading

from concurrency_manager import ConcurrencyManager

from huggingface_hub import hf_hub_download

import einops
import torch
import torch.nn as nn
import torch.nn.functional as F
import numpy as np

import imageio

from models import *
from utils import *

from transformers import T5TokenizerFast, UMT5EncoderModel

from diffusers import FlowMatchEulerDiscreteScheduler

class MyFlowMatchEulerDiscreteScheduler(FlowMatchEulerDiscreteScheduler):
    def index_for_timestep(self, timestep, schedule_timesteps=None):
        if schedule_timesteps is None:
            schedule_timesteps = self.timesteps

        return torch.argmin(
            (timestep - schedule_timesteps.to(timestep.device)).abs(), dim=0).item()

class GenerationSystem(nn.Module):
    def __init__(self, ckpt_path=None, device="cuda:0", offload_t5=False, offload_vae=False):
        super().__init__()
        self.device = device
        self.offload_t5 = offload_t5
        self.offload_vae = offload_vae

        self.latent_dim = 48
        self.temporal_downsample_factor = 4
        self.spatial_downsample_factor = 16

        self.feat_dim = 1024

        self.latent_patch_size = 2

        self.denoising_steps = [0, 250, 500, 750]

        model_id = "Wan-AI/Wan2.2-TI2V-5B-Diffusers"

        self.vae = AutoencoderKLWan.from_pretrained(model_id, subfolder="vae", torch_dtype=torch.float).eval()

        from models.autoencoder_kl_wan import WanCausalConv3d
        with torch.no_grad():
            for name, module in self.vae.named_modules():
                if isinstance(module, WanCausalConv3d):
                    time_pad = module._padding[4]
                    module.padding = (0, module._padding[2], module._padding[0])
                    module._padding = (0, 0, 0, 0, 0, 0)
                    module.weight = torch.nn.Parameter(module.weight[:, :, time_pad:].clone())

        self.vae.requires_grad_(False)

        self.register_buffer('latents_mean', torch.tensor(self.vae.config.latents_mean).float().view(1, self.vae.config.z_dim, 1, 1, 1).to(self.device))
        self.register_buffer('latents_std', torch.tensor(self.vae.config.latents_std).float().view(1, self.vae.config.z_dim, 1, 1, 1).to(self.device))

        self.latent_scale_fn = lambda x: (x - self.latents_mean) / self.latents_std
        self.latent_unscale_fn = lambda x: x * self.latents_std + self.latents_mean

        self.tokenizer = T5TokenizerFast.from_pretrained(model_id, subfolder="tokenizer")

        self.text_encoder = UMT5EncoderModel.from_pretrained(model_id, subfolder="text_encoder", torch_dtype=torch.float32).eval().requires_grad_(False).to(self.device if not self.offload_t5 else "cpu")

        self.transformer = WanTransformer3DModel.from_pretrained(model_id, subfolder="transformer", torch_dtype=torch.float32).train().requires_grad_(False)
        
        self.transformer.patch_embedding.weight = nn.Parameter(F.pad(self.transformer.patch_embedding.weight, (0, 0, 0, 0, 0, 0, 0, 6 + self.latent_dim)))
        # self.transformer.rope.freqs_f[:] = self.transformer.rope.freqs_f[:1]

        weight = self.transformer.proj_out.weight.reshape(self.latent_patch_size ** 2, self.latent_dim, self.transformer.proj_out.weight.shape[1])
        bias = self.transformer.proj_out.bias.reshape(self.latent_patch_size ** 2, self.latent_dim)

        extra_weight = torch.randn(self.latent_patch_size ** 2, self.feat_dim, self.transformer.proj_out.weight.shape[1]) * 0.02
        extra_bias = torch.zeros(self.latent_patch_size ** 2, self.feat_dim)
 
        self.transformer.proj_out.weight = nn.Parameter(torch.cat([weight, extra_weight], dim=1).flatten(0, 1).detach().clone())
        self.transformer.proj_out.bias = nn.Parameter(torch.cat([bias, extra_bias], dim=1).flatten(0, 1).detach().clone())

        self.recon_decoder = WANDecoderPixelAligned3DGSReconstructionModel(self.vae, self.feat_dim, use_render_checkpointing=True, use_network_checkpointing=False).train().requires_grad_(False).to(self.device)

        self.scheduler = MyFlowMatchEulerDiscreteScheduler.from_pretrained(model_id, subfolder="scheduler", shift=3)

        self.register_buffer('timesteps', self.scheduler.timesteps.clone().to(self.device))

        self.transformer.disable_gradient_checkpointing()
        self.transformer.gradient_checkpointing = False

        self.add_feedback_for_transformer()

        if ckpt_path is not None:
            state_dict = torch.load(ckpt_path, map_location="cpu", weights_only=False)
            self.transformer.load_state_dict(state_dict["transformer"])
            self.recon_decoder.load_state_dict(state_dict["recon_decoder"])
            print(f"Loaded {ckpt_path}.")

        from quant import FluxFp8GeMMProcessor

        FluxFp8GeMMProcessor(self.transformer)

        del self.vae.post_quant_conv, self.vae.decoder
        self.vae.to(self.device if not self.offload_vae else "cpu")

        self.transformer.to(self.device)

    def add_feedback_for_transformer(self):
        self.use_feedback = True
        self.transformer.patch_embedding.weight = nn.Parameter(F.pad(self.transformer.patch_embedding.weight, (0, 0, 0, 0, 0, 0, 0, self.feat_dim + self.latent_dim)))
    
    def encode_text(self, texts):
        max_sequence_length = 512

        text_inputs = self.tokenizer(
            texts,
            padding="max_length",
            max_length=max_sequence_length,
            truncation=True,
            add_special_tokens=True,
            return_attention_mask=True,
            return_tensors="pt",
        )
        if getattr(self, "offload_t5", False):
            text_input_ids = text_inputs.input_ids.to("cpu")
            mask = text_inputs.attention_mask.to("cpu")
        else:
            text_input_ids = text_inputs.input_ids.to(self.device)
            mask = text_inputs.attention_mask.to(self.device)
        seq_lens = mask.gt(0).sum(dim=1).long()

        if getattr(self, "offload_t5", False):
            with torch.no_grad():
                text_embeds = self.text_encoder(text_input_ids, mask).last_hidden_state.to(self.device)
        else:
            text_embeds = self.text_encoder(text_input_ids, mask).last_hidden_state
        text_embeds = [u[:v] for u, v in zip(text_embeds, seq_lens)]
        text_embeds = torch.stack(
            [torch.cat([u, u.new_zeros(max_sequence_length - u.size(0), u.size(1))]) for u in text_embeds], dim=0
        )
        return text_embeds.float()

    def forward_generator(self, noisy_latents, raymaps, condition_latents, t, text_embeds, cameras, render_cameras, image_height, image_width, need_3d_mode=True):

        out = self.transformer(
            hidden_states=torch.cat([noisy_latents, raymaps, condition_latents], dim=1),
            timestep=t,
            encoder_hidden_states=text_embeds,
            return_dict=False,
        )[0]

        v_pred, feats = out.split([self.latent_dim, self.feat_dim], dim=1)
               
        sigma = torch.stack([self.scheduler.sigmas[self.scheduler.index_for_timestep(_t)] for _t in t.unbind(0)], dim=0).to(self.device)
        latents_pred_2d = noisy_latents - sigma * v_pred

        if need_3d_mode:
            scene_params = self.recon_decoder(
                                einops.rearrange(feats, 'B C T H W -> (B T) C H W').unsqueeze(2), 
                                einops.rearrange(self.latent_unscale_fn(latents_pred_2d.detach()), 'B C T H W -> (B T) C H W').unsqueeze(2), 
                                cameras
                            ).flatten(1, -2)

            images_pred, _ = self.recon_decoder.render(scene_params.unbind(0), render_cameras, image_height, image_width, bg_mode="white")

            latents_pred_3d = einops.rearrange(self.latent_scale_fn(self.vae.encode(
                            einops.rearrange(images_pred, 'B T C H W -> (B T) C H W', T=images_pred.shape[1]).unsqueeze(2).to(self.device if not self.offload_vae else "cpu").float()
                        ).latent_dist.sample().to(self.device)).squeeze(2), '(B T) C H W -> B C T H W', T=images_pred.shape[1]).to(noisy_latents.dtype)

        return {
            '2d': latents_pred_2d,
            '3d': latents_pred_3d if need_3d_mode else None,
            'rgb_3d': images_pred if need_3d_mode else None,
            'scene': scene_params if need_3d_mode else None,
            'feat': feats
        }

    @torch.no_grad()
    @torch.amp.autocast(dtype=torch.bfloat16, device_type="cuda")
    def generate(self, cameras, n_frame, image=None, text="", image_index=0, image_height=480, image_width=704, video_output_path=None):            
        with torch.no_grad():
            batch_size = 1
            
            cameras = cameras.to(self.device).unsqueeze(0)

            if cameras.shape[1] != n_frame:
                render_cameras = cameras.clone()
                cameras = sample_from_dense_cameras(cameras.squeeze(0), torch.linspace(0, 1, n_frame, device=self.device)).unsqueeze(0)
            else:
                render_cameras = cameras
            
            cameras, ref_w2c, T_norm = normalize_cameras(cameras, return_meta=True, n_frame=None)

            render_cameras = normalize_cameras(render_cameras, ref_w2c=ref_w2c, T_norm=T_norm, n_frame=None)

            text = "[Static] " + text

            text_embeds = self.encode_text([text])
            # neg_text_embeds = self.encode_text([""]).repeat(batch_size, 1, 1)

            masks = torch.zeros(batch_size, n_frame, device=self.device)

            condition_latents = torch.zeros(batch_size, self.latent_dim, n_frame, image_height // self.spatial_downsample_factor, image_width // self.spatial_downsample_factor, device=self.device)

            if image is not None:
                image = image.to(self.device)

                latent = self.latent_scale_fn(self.vae.encode(
                        image.unsqueeze(0).unsqueeze(2).to(self.device if not self.offload_vae else "cpu").float()
                    ).latent_dist.sample().to(self.device)).squeeze(2)

                masks[:, image_index] = 1
                condition_latents[:, :, image_index] = latent

            raymaps = create_raymaps(cameras, image_height // self.spatial_downsample_factor, image_width // self.spatial_downsample_factor)
            raymaps = einops.rearrange(raymaps, 'B T H W C -> B C T H W', T=n_frame)
            
            noise = torch.randn(batch_size, self.latent_dim, n_frame, image_height // self.spatial_downsample_factor, image_width // self.spatial_downsample_factor, device=self.device)

            noisy_latents = noise 

            torch.cuda.empty_cache()

            if self.use_feedback:
                prev_latents_pred = torch.zeros(batch_size, self.latent_dim, n_frame, image_height // self.spatial_downsample_factor, image_width // self.spatial_downsample_factor, device=self.device)

                prev_feats = torch.zeros(batch_size, self.feat_dim, n_frame, image_height // self.spatial_downsample_factor, image_width // self.spatial_downsample_factor, device=self.device)

            for i in range(len(self.denoising_steps)):
                t_ids = torch.full((noisy_latents.shape[0],), self.denoising_steps[i], device=self.device)

                t = self.timesteps[t_ids]

                if self.use_feedback:
                    _condition_latents = torch.cat([condition_latents, prev_feats, prev_latents_pred], dim=1)
                else:
                    _condition_latents = condition_latents

                if i < len(self.denoising_steps) - 1:
                    out = self.forward_generator(noisy_latents, raymaps, _condition_latents, t, text_embeds, cameras, cameras, image_height, image_width, need_3d_mode=True)

                    latents_pred = out["3d"]

                    if self.use_feedback:
                        prev_latents_pred = latents_pred
                        prev_feats = out['feat']
                   
                    noisy_latents = self.scheduler.scale_noise(latents_pred, self.timesteps[torch.full((noisy_latents.shape[0],), self.denoising_steps[i + 1], device=self.device)], torch.randn_like(noise))
                    
                else:
                    out = self.transformer(
                        hidden_states=torch.cat([noisy_latents, raymaps, _condition_latents], dim=1),
                        timestep=t,
                        encoder_hidden_states=text_embeds,
                        return_dict=False,
                    )[0]

                    v_pred, feats = out.split([self.latent_dim, self.feat_dim], dim=1)
                        
                    sigma = torch.stack([self.scheduler.sigmas[self.scheduler.index_for_timestep(_t)] for _t in t.unbind(0)], dim=0).to(self.device)
                    latents_pred = noisy_latents - sigma * v_pred

                    scene_params = self.recon_decoder(
                                        einops.rearrange(feats, 'B C T H W -> (B T) C H W').unsqueeze(2), 
                                        einops.rearrange(self.latent_unscale_fn(latents_pred.detach()), 'B C T H W -> (B T) C H W').unsqueeze(2), 
                                        cameras
                                    ).flatten(1, -2)

            if video_output_path is not None:
                interpolated_images_pred, _ = self.recon_decoder.render(scene_params.unbind(0), render_cameras, image_height, image_width, bg_mode="white")

                interpolated_images_pred = einops.rearrange(interpolated_images_pred[0].clamp(-1, 1).add(1).div(2), 'T C H W -> T H W C')

                interpolated_images_pred = [torch.cat([img], dim=1).detach().cpu().mul(255).numpy().astype(np.uint8) for i, img in enumerate(interpolated_images_pred.unbind(0))]

                imageio.mimwrite(video_output_path, interpolated_images_pred, fps=15, quality=8, macro_block_size=1) 

        scene_params = scene_params[0]    

        scene_params = scene_params.detach().cpu()

        return scene_params, ref_w2c, T_norm

if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument('--port', type=int, default=7860)
    parser.add_argument("--ckpt", default=None)
    parser.add_argument("--gpu", type=int, default=0)
    parser.add_argument("--cache_dir", type=str, default="./tmpfiles")
    parser.add_argument("--offload_t5", type=bool, default=False)
    parser.add_argument("--max_concurrent", type=int, default=1, help="Maximum concurrent generation tasks")
    args, _ = parser.parse_known_args()

    # Ensure model.ckpt exists, download if not present
    if args.ckpt is None:
        from huggingface_hub.constants import HUGGINGFACE_HUB_CACHE
        ckpt_path = os.path.join(HUGGINGFACE_HUB_CACHE, "models--imlixinyang--FlashWorld", "snapshots", "6a8e88c6f88678ac098e4c82675f0aee555d6e5d", "model.ckpt")
        if not os.path.exists(ckpt_path):
            hf_hub_download(repo_id="imlixinyang/FlashWorld", filename="model.ckpt", local_dir_use_symlinks=False)
    else:
        ckpt_path = args.ckpt

    app = Flask(__name__)
    
    # 初始化GenerationSystem
    device = f"cuda:{args.gpu}" if torch.cuda.is_available() else "cpu"
    generation_system = GenerationSystem(ckpt_path=ckpt_path, device=device)
    
    # 初始化并发管理器
    concurrency_manager = ConcurrencyManager(max_concurrent=args.max_concurrent)

    @app.after_request
    def after_request(response):
        response.headers.add('Access-Control-Allow-Origin', '*')
        response.headers.add('Access-Control-Allow-Headers', 'Content-Type,Authorization')
        response.headers.add('Access-Control-Allow-Methods', 'GET,PUT,POST,DELETE,OPTIONS')
        return response
    
    @GPU
    def generate_wrapper(cameras, n_frame, image, text_prompt, image_index, image_height, image_width, video_output_path=None):
        """生成函数的包装器，用于并发控制"""
        return generation_system.generate(cameras, n_frame, image, text_prompt, image_index, image_height, image_width, video_output_path)

    def job_generate(file_id, cache_dir, payload):
        """工作线程执行的生成任务：负责生成并落盘，返回可下载信息"""
        # 解包参数
        cameras = payload["cameras"]
        n_frame = payload["n_frame"]
        image = payload["image"]
        text_prompt = payload["text_prompt"]
        image_index = payload["image_index"]
        image_height = payload["image_height"]
        image_width = payload["image_width"]
        data = payload["raw_request"]

        # 执行生成
        scene_params, ref_w2c, T_norm = generation_system.generate(
            cameras, n_frame, image, text_prompt, image_index, image_height, image_width, video_output_path=None
        )

        # 保存请求元数据
        with open(os.path.join(cache_dir, f'{file_id}.json'), 'w') as f:
            json.dump(data, f)

        # 导出PLY文件
        splat_path = os.path.join(cache_dir, f'{file_id}.ply')
        export_ply_for_gaussians(splat_path, scene_params, opacity_threshold=0.001, T_norm=T_norm)

        file_size = os.path.getsize(splat_path) if os.path.exists(splat_path) else 0

        return {
            'file_id': file_id,
            'file_path': splat_path,
            'file_size': file_size,
            'download_url': f'/download/{file_id}'
        }
    
    @app.route('/generate', methods=['POST', 'OPTIONS'])
    def generate():
        # Handle preflight request
        if request.method == 'OPTIONS':
            return jsonify({'status': 'ok'})
        
        try:
            data = request.get_json(force=True)
            
            image_prompt = data.get('image_prompt', None)
            text_prompt = data.get('text_prompt', "")
            cameras = data.get('cameras')
            resolution = data.get('resolution')
            image_index = data.get('image_index', 0)

            n_frame, image_height, image_width = resolution

            if not image_prompt and text_prompt == "":
                return jsonify({'error': 'No Prompts provided'}), 400

            # 处理图像
            if image_prompt:
                # image_prompt可以是路径和base64
                if os.path.exists(image_prompt):
                    image_prompt = Image.open(image_prompt)
                else:
                    # image_prompt 可能是 "data:image/png;base64,...."
                    if ',' in image_prompt:
                        image_prompt = image_prompt.split(',', 1)[1]
                    
                    try:
                        image_bytes = base64.b64decode(image_prompt)
                        image_prompt = Image.open(io.BytesIO(image_bytes))
                    except Exception as img_e:
                        return jsonify({'error': f'Image decode error: {str(img_e)}'}), 400

                image = image_prompt.convert('RGB')

                w, h = image.size

                # center crop
                if image_height / h > image_width / w:
                    scale = image_height / h
                else:
                    scale = image_width / w
                    
                new_h = int(image_height / scale)
                new_w = int(image_width / scale)

                image = image.crop(((w - new_w) // 2, (h - new_h) // 2, 
                                    new_w + (w - new_w) // 2, new_h + (h - new_h) // 2)).resize((image_width, image_height))

                for camera in cameras:
                    camera['fx'] = camera['fx'] * scale 
                    camera['fy'] = camera['fy'] * scale 
                    camera['cx'] = (camera['cx'] - (w - new_w) // 2) * scale
                    camera['cy'] = (camera['cy'] - (h - new_h) // 2) * scale

                image = torch.from_numpy(np.array(image)).float().permute(2, 0, 1) / 255.0 * 2 - 1
            else:
                image = None

            cameras = torch.stack([
                torch.from_numpy(np.array([camera['quaternion'][0], camera['quaternion'][1], camera['quaternion'][2], camera['quaternion'][3], camera['position'][0], camera['position'][1], camera['position'][2], camera['fx'] / image_width, camera['fy'] / image_height, camera['cx'] / image_width, camera['cy'] / image_height], dtype=np.float32))
                for camera in cameras
            ], dim=0)

            file_id = str(int(time.time() * 1000))

            # 组装任务参数，推迟执行与落盘到工作线程中
            payload = {
                'cameras': cameras,
                'n_frame': n_frame,
                'image': image,
                'text_prompt': text_prompt,
                'image_index': image_index,
                'image_height': image_height,
                'image_width': image_width,
                'raw_request': data,
            }

            # 提交任务到并发管理器（异步）
            task_id = concurrency_manager.submit_task(
                job_generate, file_id, args.cache_dir, payload
            )

            # 提交后立即返回队列信息
            queue_status = concurrency_manager.get_queue_status()
            queued_tasks = queue_status.get('queued_tasks', [])
            try:
                queue_position = queued_tasks.index(task_id) + 1
            except ValueError:
                # 如果任务已被工作线程立即领取，则认为已开始执行，位置为 0
                queue_position = 0

            return jsonify({
                'success': True,
                'task_id': task_id,
                'file_id': file_id,
                'queue': {
                    'queued_count': queue_status.get('queued_count', 0),
                    'running_count': queue_status.get('running_count', 0),
                    'position': queue_position
                }
            }), 202
                
        except Exception as e:
            return jsonify({'error': f'Server error: {str(e)}'}), 500

    @app.route('/download/<file_id>', methods=['GET'])
    def download_file(file_id):
        """下载生成的PLY文件"""
        file_path = os.path.join(args.cache_dir, f'{file_id}.ply')
        
        if not os.path.exists(file_path):
            return jsonify({'error': 'File not found'}), 404
        
        return send_file(file_path, as_attachment=True, download_name=f'{file_id}.ply')

    @app.route('/delete/<file_id>', methods=['DELETE', 'POST', 'OPTIONS'])
    def delete_file_endpoint(file_id):
        """删除生成的文件及其元数据（由前端在下载完成后调用）"""
        # CORS preflight
        if request.method == 'OPTIONS':
            return jsonify({'status': 'ok'})

        try:
            ply_path = os.path.join(args.cache_dir, f'{file_id}.ply')
            json_path = os.path.join(args.cache_dir, f'{file_id}.json')
            deleted = []
            for path in [ply_path, json_path]:
                if os.path.exists(path):
                    os.remove(path)
                    deleted.append(os.path.basename(path))
            return jsonify({'success': True, 'deleted': deleted})
        except Exception as e:
            return jsonify({'success': False, 'error': str(e)}), 500
    
    @app.route('/status', methods=['GET'])
    def get_status():
        """获取系统状态和队列信息"""
        try:
            queue_status = concurrency_manager.get_queue_status()
            return jsonify({
                'success': True,
                'status': queue_status,
                'timestamp': time.time()
            })
        except Exception as e:
            return jsonify({'error': f'Failed to get status: {str(e)}'}), 500
    
    @app.route('/task/<task_id>', methods=['GET'])
    def get_task_status(task_id):
        """获取特定任务的状态（包含排队位置和完成后的文件信息）"""
        try:
            task = concurrency_manager.get_task_status(task_id)
            if not task:
                return jsonify({'error': 'Task not found'}), 404

            queue_status = concurrency_manager.get_queue_status()
            queued_tasks = queue_status.get('queued_tasks', [])
            try:
                queue_position = queued_tasks.index(task_id) + 1
            except ValueError:
                queue_position = 0

            resp = {
                'success': True,
                'task_id': task_id,
                'status': task.status.value,
                'created_at': task.created_at,
                'started_at': task.started_at,
                'completed_at': task.completed_at,
                'error': task.error,
                'queue': {
                    'queued_count': queue_status.get('queued_count', 0),
                    'running_count': queue_status.get('running_count', 0),
                    'position': queue_position
                }
            }

            if task.status.value == 'completed' and isinstance(task.result, dict):
                resp.update({
                    'file_id': task.result.get('file_id'),
                    'file_path': task.result.get('file_path'),
                    'file_size': task.result.get('file_size'),
                    'download_url': task.result.get('download_url'),
                    'generation_time': (task.completed_at - task.started_at)
                })

                # 更新task状态

            return jsonify(resp)
        except Exception as e:
            return jsonify({'error': f'Failed to get task status: {str(e)}'}), 500

    @app.route("/")
    def index():
        return send_file("index.html")

    os.makedirs(args.cache_dir, exist_ok=True)

    # 后台定时清理：删除超过30分钟未访问/修改的缓存文件
    def cleanup_worker(cache_dir: str, max_age_seconds: int = 1800, interval_seconds: int = 300):
        while True:
            try:
                now = time.time()
                for name in os.listdir(cache_dir):
                    # 只清理与任务相关的 .ply/.json 文件
                    if not (name.endswith('.ply') or name.endswith('.json')):
                        continue
                    path = os.path.join(cache_dir, name)
                    try:
                        mtime = os.path.getmtime(path)
                        if now - mtime > max_age_seconds:
                            os.remove(path)
                    except FileNotFoundError:
                        pass
                    except Exception:
                        # 忽略单个文件的异常，继续清理
                        pass
            except Exception:
                # 防止线程因异常退出
                pass
            time.sleep(interval_seconds)

    cleaner_thread = threading.Thread(target=cleanup_worker, args=(args.cache_dir,), daemon=True)
    cleaner_thread.start()

    app.run(host='0.0.0.0', port=args.port)